diff --git a/Cargo.toml b/Cargo.toml
index 6367269..fc39e57 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,12 +12,13 @@ readme = "README.md"
 ff = {package="ff_ce", version= "0.11", features = ["derive"]}
 rand_new = {package="rand", version="0.8.5"}
 rand = "0.4.6"
+# rand = "0.8"
 num = "0.4"
 num-bigint = {version = "0.4", features = ["rand"]}
 num-traits = "0.2.8"
-blake2 = "0.10.6"
-# blake-hash = {version="0.4.0", optional=true}
-# blake = {version="2.0.1", optional=true}
+# blake2 = "0.10.6"
+blake-hash = {version="0.4.0", optional=true}
+blake = {version="2.0.1", optional=true}
 generic-array = "0.14"
 poseidon-rs = "0.0.8"
 arrayref = "0.3.5"
@@ -34,6 +35,6 @@ hex = "0.4"
 name = "bench_babyjubjub"
 harness = false
 
-# [features]
-# default = ["blake-hash"]
-# aarch64 = ["blake"]
+[features]
+default = ["blake-hash"]
+aarch64 = ["blake"]
diff --git a/src/lib.rs b/src/lib.rs
index e7c64e2..9946f70 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -6,15 +6,12 @@ use rand::ThreadRng;
 use std::{iter::Sum, ops::{Neg, AddAssign}, fmt::Error};
 use num::Num;
 use std::fmt;
-// use serde::{Serialize, ser::SerializeSeq, Deserialize};
 use serde::{Serialize, ser::SerializeStruct, de::Visitor, de::MapAccess, Deserialize, Deserializer};
-// use bytes::{BytesMut, BufMut};
 use poseidon_rs::Poseidon;
 pub type Fr = poseidon_rs::Fr; // alias
 
 extern crate rand_new;
 extern crate rand;
-// #[macro_use]
 extern crate ff;
 
 // Create a new primefield for the subgroup defined by the base point, order Fl:
@@ -25,13 +22,12 @@ pub struct Fl(FpRepr);
 
 use arrayref::array_ref;
 
-// #[cfg(not(feature = "aarch64"))]
-// use blake_hash::Digest; // compatible version with Blake used at circomlib
+#[cfg(not(feature = "aarch64"))]
+use blake_hash::Digest; // compatible version with Blake used at circomlib
+
+#[cfg(feature = "aarch64")]
+extern crate blake; // compatible version with Blake used at circomlib
 
-// #[cfg(feature = "aarch64")]
-// extern crate blake; // compatible version with Blake used at circomlib
-use blake2::{Blake2b512, Digest};
-// use hex_literal::hex;
 use std::{cmp::min, str::FromStr};
 
 use num_bigint::{BigInt, RandBigInt, Sign, ToBigInt};
@@ -502,30 +498,29 @@ pub fn decompress_point(bb: [u8; 32]) -> Result<Point, String> {
     Ok(Point { x: x_fr, y: y_fr })
 }
 
-// #[cfg(not(feature = "aarch64"))]
-// fn blh(b: &[u8]) -> Vec<u8> {
-//     println!("hashing {:?} {:?}", b.len(), b);
-//     let debugggggggggme = blake_hash::Blake512::digest(b);
-//     println!("debugging {:?}", debugggggggggme);
+#[cfg(not(feature = "aarch64"))]
+fn blh(b: &[u8]) -> Vec<u8> {
+    // println!("hashing {:?} {:?}", b.len(), b);
+    // let debugggggggggme = blake_hash::Blake512::digest(b);
+    // println!("debugging {:?}", debugggggggggme);
+    let hash = blake_hash::Blake512::digest(b);
+    hash.to_vec()
+}
 
-//     let hash = blake_hash::Blake512::digest(b);
-//     hash.to_vec()
-// }
+#[cfg(feature = "aarch64")]
+fn blh(b: &[u8]) -> Vec<u8> {
+    let mut hash = [0; 64];
+    blake::hash(512, b, &mut hash).unwrap();
+    hash.to_vec()
+}
 
-// #[cfg(feature = "aarch64")]
-// fn blh(b: &[u8]) -> Vec<u8> {
-//     let mut hash = [0; 64];
-//     blake::hash(512, b, &mut hash).unwrap();
-//     hash.to_vec()
+// pub fn blh(b: &[u8]) -> Vec<u8> {
+//     let mut h = Blake2b512::new();
+//     h.update(b);
+//     let digest = h.finalize();
+//     return digest[..].to_vec();
 // }
 
-pub fn blh(b: &[u8]) -> Vec<u8> {
-    let mut h = Blake2b512::new();
-    h.update(b);
-    let digest = h.finalize();
-    return digest[..].to_vec();
-}
-
 #[derive(Debug, Clone, Serialize)]
 pub struct Signature {
     pub r_b8: Point,